If you have the Rasmol source I'd suggest to edit the Imakefile appropiately. # DEPTHDEF = -DTHIRTYTWOBIT # DEPTHDEF = -DEIGHTBIT DEPTHDEF = -DSIXTEENBIT Or to avoid another run of imake do the change directly in the Makefile. I can supply you with the 16bit version if you have any problems. Steffen -- Steffen Moeller <moeller at ebi.ac.uk>